It's a wet Friday across the MLB, with a full slate of games in theory, but a few of them unlikely to actually be played. We'll try to avoid the worst of the bunch, since the impact of a cold/wet start is hard to quantify — but we still have a handful of picks for the day.
The Model
The process is relatively simple. First, I start by assuming that the full game (implied) run totals for either team are roughly efficient. As mentioned above, that tends to be the case more often than not. This saves me the trouble of trying to predict the total runs scored in the game — and allows me to focus strictly on the "when" rather than "how many."
Next, I built a database of pitchers performance the first time through the order, relative to their overall stats. Since the latter is presumably baked into the full game total, I wanted to figure out if those runs are more likely to come early or late. Most — but not all — MLB starters do somewhat better early in games, but with some variance in just how much. The model uses xFIP (expected Fielding Independent Pitching) as the ERA predictor of choice.
That's only half of the equation, though, with the offenses making up the other half. To do this, I looked at what percentage of a team's total runs is produced by the top three batters in the lineup. While a first inning run scored, by definition, needs at least four hitters to come to the plate, one of the first three has to actually score it. The metric of choice here is wRC+, based on the projected lineup for the day from each team.
This is a bit of a tradeoff, as lineups (and run totals) can shift throughout the day, especially if significant contributors miss time. However, in my experience the inefficiency of the morning lines more than makes up for the leakage in the model. With that said, exercise caution if, say, Mike Trout is listed as questionable for the nights game.
The Picks
With all of the picks below, I'll include the pick, the best line and the threshold I'd bet it to. These will go up in the morning, so if any major news breaks between publishing and when you read it, be sure to consider that.
Infrequently, rather than betting on the traditional YRFI/NRFI, the pick will be on one team or the other specifically to score a run, which as of this writing is only a betting option at DraftKings. Since the model handles each team individually, sometimes one team is projecting for a greater proportion of the "run equity" in the first inning than the betting lines are accounting for.
NRFI Odds, Picks for Friday, April 28
Seattle Mariners vs. Toronto Blue Jays NRFI: This game is strength on strength, with two solid offenses facing off with two upper-tier pitchers. Both arms have excellent splits the first time through the order though, more than enough to overcome the 8.5-run total.
Cleveland Guardians vs. Boston Red Sox YRFI: Regression has hit Shane Bieber a bit already, but he's due for even more — his xERA is more than two runs higher than his ERA this season. He's also slightly worse his first pass through the order in his career, with Sox starter Nick Pivetta also below average in that regard.
Philadelphia Phillies vs. Houston Astros NRFI: This is a fairly generous line for a game with a 7.5-run total. Two solid starters, and both offenses on the wrong side of their platoon splits.
Pick: Phillies vs. Astros NRFI (-125) |
ArizonaDiamondbacks vs. Colorado Rockies YRFI: I don't love laying the juice on these Coors games, but the 11-run total has it popping in my model. This projects at nearly a 70% chance of a run in the first inning, with implied odds at BetMGM under 60%.
